The U.S. Environmental Protection Agency released a proposed plan to clean up the Lower Duwamish Waterway Superfund Site… The release of the sediment cleanup plan marks the beginning of a public comment period… The proposed plan calls for cleanup of the most contaminated sediment and would reduce PCB contamination in the waterway by at least 90 percent… However, the agency’s Community Advisory Group for the project says the plan needs work to protect some whose health will still be threatened by pollutants in the river.